2 /* pngconf.h - machine configurable file for libpng
5 * For conditions of distribution and use, see copyright notice in png.h
6 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
7 * Copyright (c) 1996, 1997 Andreas Dilger
8 * Copyright (c) 1998, Glenn Randers-Pehrson
12 /* Any machine specific code is near the front of this file, so if you
13 * are configuring libpng for a machine, you may want to read the section
14 * starting here down to where it starts to typedef png_color, png_text,
21 /* This is the size of the compression buffer, and thus the size of
22 * an IDAT chunk. Make this whatever size you feel is best for your
23 * machine. One of these will be allocated per png_struct. When this
24 * is full, it writes the data to the disk, and does some other
25 * calculations. Making this an extremely small size will slow
26 * the library down, but you may want to experiment to determine
27 * where it becomes significant, if you are concerned with memory
28 * usage. Note that zlib allocates at least 32Kb also. For readers,
29 * this describes the size of the buffer available to read the data in.
30 * Unless this gets smaller than the size of a row (compressed),
31 * it should not make much difference how big this is.
35 #define PNG_ZBUF_SIZE 8192
38 /* If you are running on a machine where you cannot allocate more
39 * than 64K of memory at once, uncomment this. While libpng will not
40 * normally need that much memory in a chunk (unless you load up a very
41 * large file), zlib needs to know how big of a chunk it can use, and
42 * libpng thus makes sure to check any memory allocation to verify it
43 * will fit into memory.
44 #define PNG_MAX_MALLOC_64K
46 #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
47 #define PNG_MAX_MALLOC_64K
50 /* This protects us against compilers which run on a windowing system
51 * and thus don't have or would rather us not use the stdio types:
52 * stdin, stdout, and stderr. The only one currently used is stderr
53 * in png_error() and png_warning(). #defining PNG_NO_STDIO will
54 * prevent these from being compiled and used.
55 * #define PNG_NO_STDIO
62 /* This macro protects us against machines that don't have function
63 * prototypes (ie K&R style headers). If your compiler does not handle
64 * function prototypes, define this macro and use the included ansi2knr.
65 * I've always been able to use _NO_PROTO as the indicator, but you may
66 * need to drag the empty declaration out in front of here, or change the
67 * ifdef to suit your own needs.
71 #ifdef OF /* zlib prototype munger */
72 #define PNGARG(arglist) OF(arglist)
76 #define PNGARG(arglist) ()
78 #define PNGARG(arglist) arglist
79 #endif /* _NO_PROTO */
85 /* Try to determine if we are compiling on a Mac. Note that testing for
86 * just __MWERKS__ is not good enough, because the Codewarrior is now used
87 * on non-Mac platforms.
90 #if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
91 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
96 /* enough people need this for various reasons to include it here */
97 #if !defined(MACOS) && !defined(RISCOS)
98 #include <sys/types.h>
101 /* This is an attempt to force a single setjmp behaviour on Linux. If
102 * the X config stuff didn't define _BSD_SOURCE we wouldn't need this.
106 #define _PNG_SAVE_BSD_SOURCE
110 __png
.h__ already includes setjmp
.h
111 __dont__ include it again
113 #endif /* __linux__ */
115 /* include setjmp.h for error handling */
119 #ifdef _PNG_SAVE_BSD_SOURCE
121 #undef _PNG_SAVE_BSD_SOURCE
123 #endif /* __linux__ */
131 /* Other defines for things like memory and the like can go here. */
135 /* The functions exported by PNG_EXTERN are PNG_INTERNAL functions, which
136 * aren't usually used outside the library (as far as I know), so it is
137 * debatable if they should be exported at all. In the future, when it is
138 * possible to have run-time registry of chunk-handling functions, some of
139 * these will be made available again.
140 #define PNG_EXTERN extern
144 /* Other defines specific to compilers can go here. Try to keep
145 * them inside an appropriate ifdef/endif pair for portability.
149 /* We need to check that <math.h> hasn't already been included earlier
150 * as it seems it doesn't agree with <fp.h>, yet we should really use
151 * <fp.h> if possible.
153 #if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
160 /* Codewarrior on NT has linking problems without this. */
161 #if defined(__MWERKS__) && defined(WIN32)
162 #define PNG_ALWAYS_EXTERN
165 /* For some reason, Borland C++ defines memcmp, etc. in mem.h, not
166 * stdlib.h like it should (I think). Or perhaps this is a C++
178 /* This controls how fine the dithering gets. As this allocates
179 * a largish chunk of memory (32K), those who are not as concerned
180 * with dithering quality can decrease some or all of these.
182 #ifndef PNG_DITHER_RED_BITS
183 #define PNG_DITHER_RED_BITS 5
185 #ifndef PNG_DITHER_GREEN_BITS
186 #define PNG_DITHER_GREEN_BITS 5
188 #ifndef PNG_DITHER_BLUE_BITS
189 #define PNG_DITHER_BLUE_BITS 5
192 /* This controls how fine the gamma correction becomes when you
193 * are only interested in 8 bits anyway. Increasing this value
194 * results in more memory being used, and more pow() functions
195 * being called to fill in the gamma tables. Don't set this value
196 * less then 8, and even that may not work (I haven't tested it).
199 #ifndef PNG_MAX_GAMMA_8
200 #define PNG_MAX_GAMMA_8 11
203 /* This controls how much a difference in gamma we can tolerate before
204 * we actually start doing gamma conversion.
206 #ifndef PNG_GAMMA_THRESHOLD
207 #define PNG_GAMMA_THRESHOLD 0.05
210 #endif /* PNG_INTERNAL */
212 /* The following uses const char * instead of char * for error
213 * and warning message functions, so some compilers won't complain.
214 * If you do not want to use const, define PNG_NO_CONST here.
218 # define PNG_CONST const
223 /* The following defines give you the ability to remove code from the
224 * library that you will not be using. I wish I could figure out how to
225 * automate this, but I can't do that without making it seriously hard
226 * on the users. So if you are not using an ability, change the #define
227 * to and #undef, and that part of the library will not be compiled. If
228 * your linker can't find a function, you may want to make sure the
229 * ability is defined here. Some of these depend upon some others being
230 * defined. I haven't figured out all the interactions here, so you may
231 * have to experiment awhile to get everything to compile. If you are
232 * creating or using a shared library, you probably shouldn't touch this,
233 * as it will affect the size of the structures, and this will cause bad
234 * things to happen if the library and/or application ever change.
237 /* Any transformations you will not be using can be undef'ed here */
239 /* GR-P, 0.96a: Set "*TRANSFORMS_SUPPORTED as default but allow user
240 to turn it off with "*TRANSFORMS_NOT_SUPPORTED" on the compile line,
241 then pick and choose which ones to define without having to edit
242 this file. It is safe to use the *TRANSFORMS_NOT_SUPPORTED if you
243 only want to have a png-compliant reader/writer but don't need
244 any of the extra transformations. This saves about 80 kbytes in a
245 typical installation of the library.
249 #ifndef PNG_READ_TRANSFORMS_NOT_SUPPORTED
250 #define PNG_READ_TRANSFORMS_SUPPORTED
252 #ifndef PNG_WRITE_TRANSFORMS_NOT_SUPPORTED
253 #define PNG_WRITE_TRANSFORMS_SUPPORTED
256 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
257 #define PNG_READ_EXPAND_SUPPORTED
258 #define PNG_READ_SHIFT_SUPPORTED
259 #define PNG_READ_PACK_SUPPORTED
260 #define PNG_READ_BGR_SUPPORTED
261 #define PNG_READ_SWAP_SUPPORTED
262 #define PNG_READ_PACKSWAP_SUPPORTED
263 #define PNG_READ_INVERT_SUPPORTED
264 #define PNG_READ_DITHER_SUPPORTED
265 #define PNG_READ_BACKGROUND_SUPPORTED
266 #define PNG_READ_16_TO_8_SUPPORTED
267 #define PNG_READ_FILLER_SUPPORTED
268 #define PNG_READ_GAMMA_SUPPORTED
269 #define PNG_READ_GRAY_TO_RGB_SUPPORTED
270 #define PNG_READ_SWAP_ALPHA_SUPPORTED
271 #define PNG_READ_INVERT_ALPHA_SUPPORTED
272 #define PNG_READ_STRIP_ALPHA_SUPPORTED
273 #define PNG_READ_USER_TRANSFORM_SUPPORTED
274 /* the following aren't implemented yet
275 #define PNG_READ_RGB_TO_GRAY_SUPPORTED
277 #endif /* PNG_READ_TRANSFORMS_SUPPORTED */
279 #ifndef PNG_PROGRESSIVE_READ_NOT_SUPPORTED /* if you don't do progressive */
280 #define PNG_PROGRESSIVE_READ_SUPPORTED /* reading. This is not talking */
281 #endif /* about interlacing capability! You'll */
282 /* still have interlacing unless you change the following line: */
283 #define PNG_READ_INTERLACING_SUPPORTED /* required for PNG-compliant decoders */
284 #define PNG_READ_COMPOSITE_NODIV_SUPPORTED /* well tested on Intel and SGI */
286 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
287 #define PNG_WRITE_SHIFT_SUPPORTED
288 #define PNG_WRITE_PACK_SUPPORTED
289 #define PNG_WRITE_BGR_SUPPORTED
290 #define PNG_WRITE_SWAP_SUPPORTED
291 #define PNG_WRITE_PACKSWAP_SUPPORTED
292 #define PNG_WRITE_INVERT_SUPPORTED
293 #define PNG_WRITE_FILLER_SUPPORTED /* This is the same as WRITE_STRIP_ALPHA */
294 #define PNG_WRITE_FLUSH_SUPPORTED
295 #define PNG_WRITE_SWAP_ALPHA_SUPPORTED
296 #define PNG_WRITE_INVERT_ALPHA_SUPPORTED
297 #define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
298 #define PNG_WRITE_USER_TRANSFORM_SUPPORTED
299 #endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
301 #define PNG_WRITE_INTERLACING_SUPPORTED /* not required for PNG-compliant
302 encoders, but can cause trouble
305 #if !defined(PNG_NO_STDIO)
306 #define PNG_TIME_RFC1123_SUPPORTED
309 /* This adds extra functions in pngget.c for accessing data from the
310 * info pointer (added in version 0.99)
311 * png_get_image_width()
312 * png_get_image_height()
313 * png_get_bit_depth()
314 * png_get_color_type()
315 * png_get_compression_type()
316 * png_get_filter_type()
317 * png_get_interlace_type()
318 * png_get_pixel_aspect_ratio()
319 * png_get_pixels_per_meter()
320 * png_get_x_offset_pixels()
321 * png_get_y_offset_pixels()
322 * png_get_x_offset_microns()
323 * png_get_y_offset_microns()
325 #if !defined(PNG_NO_EASY_ACCESS)
326 #define PNG_EASY_ACCESS_SUPPORTED
329 /* These are currently experimental features, define them if you want */
331 /* very little testing */
333 #define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
336 /* This is only for PowerPC big-endian and 680x0 systems */
339 #define PNG_READ_BIG_ENDIAN_SUPPORTED
342 /* These functions are turned off by default, as they will be phased out. */
344 #define PNG_USELESS_TESTS_SUPPORTED
345 #define PNG_CORRECT_PALETTE_SUPPORTED
348 /* Any chunks you are not interested in, you can undef here. The
349 * ones that allocate memory may be expecially important (hIST,
350 * tEXt, zTXt, tRNS, pCAL). Others will just save time and make png_info
354 #ifndef PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED
355 #define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
357 #ifndef PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED
358 #define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
361 #ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
362 #define PNG_READ_bKGD_SUPPORTED
363 #define PNG_READ_cHRM_SUPPORTED
364 #define PNG_READ_gAMA_SUPPORTED
365 #define PNG_READ_hIST_SUPPORTED
366 #define PNG_READ_oFFs_SUPPORTED
367 #define PNG_READ_pCAL_SUPPORTED
368 #define PNG_READ_pHYs_SUPPORTED
369 #define PNG_READ_sBIT_SUPPORTED
370 #define PNG_READ_sRGB_SUPPORTED
371 #define PNG_READ_tEXt_SUPPORTED
372 #define PNG_READ_tIME_SUPPORTED
373 #define PNG_READ_tRNS_SUPPORTED
374 #define PNG_READ_zTXt_SUPPORTED
375 #define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the optional */
376 /* PLTE chunk in RGB and RGBA images */
377 #endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */
379 #ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
380 #define PNG_WRITE_bKGD_SUPPORTED
381 #define PNG_WRITE_cHRM_SUPPORTED
382 #define PNG_WRITE_gAMA_SUPPORTED
383 #define PNG_WRITE_hIST_SUPPORTED
384 #define PNG_WRITE_oFFs_SUPPORTED
385 #define PNG_WRITE_pCAL_SUPPORTED
386 #define PNG_WRITE_pHYs_SUPPORTED
387 #define PNG_WRITE_sBIT_SUPPORTED
388 #define PNG_WRITE_sRGB_SUPPORTED
389 #define PNG_WRITE_tEXt_SUPPORTED
390 #define PNG_WRITE_tIME_SUPPORTED
391 #define PNG_WRITE_tRNS_SUPPORTED
392 #define PNG_WRITE_zTXt_SUPPORTED
393 #endif /* PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED */
395 /* need the time information for reading tIME chunks */
396 #if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
400 /* Some typedefs to get us started. These should be safe on most of the
401 * common platforms. The typedefs should be at least as large as the
402 * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
403 * don't have to be exactly that size. Some compilers dislike passing
404 * unsigned shorts as function parameters, so you may be better off using
405 * unsigned int for png_uint_16. Likewise, for 64-bit systems, you may
406 * want to have unsigned int for png_uint_32 instead of unsigned long.
409 typedef unsigned long png_uint_32
;
410 typedef long png_int_32
;
411 typedef unsigned short png_uint_16
;
412 typedef short png_int_16
;
413 typedef unsigned char png_byte
;
415 /* This is usually size_t. It is typedef'ed just in case you need it to
416 change (I'm not sure if you will or not, so I thought I'd be safe) */
417 typedef size_t png_size_t
;
419 /* The following is needed for medium model support. It cannot be in the
420 * PNG_INTERNAL section. Needs modification for other compilers besides
421 * MSC. Model independent support declares all arrays and pointers to be
422 * large using the far keyword. The zlib version used must also support
423 * model independent data. As of version zlib 1.0.4, the necessary changes
424 * have been made in zlib. The USE_FAR_KEYWORD define triggers other
425 * changes that are needed. (Tim Wegner)
428 /* Separate compiler dependencies (problem here is that zlib.h always
429 defines FAR. (SJT) */
431 #if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
437 #if !defined(__WIN32__) && !defined(__FLAT__)
438 #define PNG_MAX_MALLOC_64K
443 #define USE_FAR_KEYWORD
444 #endif /* LDATA != 1 */
446 /* Possibly useful for moving data out of default segment.
447 * Uncomment it if you want. Could also define FARDATA as
448 * const if your compiler supports it. (SJT)
451 #endif /* __WIN32__, __FLAT__ */
453 #endif /* __BORLANDC__ */
456 /* Suggest testing for specific compiler first before testing for
457 * FAR. The Watcom compiler defines both __MEDIUM__ and M_I86MM,
458 * making reliance oncertain keywords suspect. (SJT)
461 /* MSC Medium model */
463 # if defined(M_I86MM)
464 # define USE_FAR_KEYWORD
470 /* SJT: default case */
475 /* At this point FAR is always defined */
480 /* Add typedefs for pointers */
481 typedef void FAR
* png_voidp
;
482 typedef png_byte FAR
* png_bytep
;
483 typedef png_uint_32 FAR
* png_uint_32p
;
484 typedef png_int_32 FAR
* png_int_32p
;
485 typedef png_uint_16 FAR
* png_uint_16p
;
486 typedef png_int_16 FAR
* png_int_16p
;
487 typedef PNG_CONST
char FAR
* png_const_charp
;
488 typedef char FAR
* png_charp
;
489 typedef double FAR
* png_doublep
;
491 /* Pointers to pointers; i.e. arrays */
492 typedef png_byte FAR
* FAR
* png_bytepp
;
493 typedef png_uint_32 FAR
* FAR
* png_uint_32pp
;
494 typedef png_int_32 FAR
* FAR
* png_int_32pp
;
495 typedef png_uint_16 FAR
* FAR
* png_uint_16pp
;
496 typedef png_int_16 FAR
* FAR
* png_int_16pp
;
497 typedef PNG_CONST
char FAR
* FAR
* png_const_charpp
;
498 typedef char FAR
* FAR
* png_charpp
;
499 typedef double FAR
* FAR
* png_doublepp
;
501 /* Pointers to pointers to pointers; i.e. pointer to array */
502 typedef char FAR
* FAR
* FAR
* png_charppp
;
504 /* libpng typedefs for types in zlib. If zlib changes
505 * or another compression library is used, then change these.
506 * Eliminates need to change all the source files.
508 typedef charf
* png_zcharp
;
509 typedef charf
* FAR
* png_zcharpp
;
510 typedef z_stream FAR
* png_zstreamp
;
512 /* allow for compilation as dll under MS Windows */
514 #define PNG_EXPORT(type,symbol) __declspec(dllexport) type symbol
517 /* allow for compilation as dll with BORLAND C++ 5.0 */
518 #if defined(__BORLANDC__) && defined(_Windows) && defined(__DLL__)
519 # define PNG_EXPORT(type,symbol) type _export symbol
522 /* allow for compilation as shared lib under BeOS */
524 #define PNG_EXPORT(type,symbol) __declspec(export) type symbol
528 #define PNG_EXPORT(type,symbol) type symbol
532 /* User may want to use these so not in PNG_INTERNAL. Any library functions
533 * that are passed far data must be model independent.
536 #if defined(USE_FAR_KEYWORD) /* memory model independent fns */
537 /* use this to make far-to-near assignments */
540 # define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
541 # define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
542 # define png_strlen _fstrlen
543 # define png_memcmp _fmemcmp /* SJT: added */
544 # define png_memcpy _fmemcpy
545 # define png_memset _fmemset
546 #else /* use the usual functions */
547 # define CVT_PTR(ptr) (ptr)
548 # define CVT_PTR_NOCHECK(ptr) (ptr)
549 # define png_strlen strlen
550 # define png_memcmp memcmp /* SJT: added */
551 # define png_memcpy memcpy
552 # define png_memset memset
554 /* End of memory model independent support */
556 /* Just a double check that someone hasn't tried to define something
559 #if (PNG_ZBUF_SIZE > 65536) && defined(PNG_MAX_MALLOC_64K)
561 #define PNG_ZBUF_SIZE 65536
564 #endif /* PNGCONF_H */